I'm surprised at the rather complete status of the wreckage's, depending on altitude lost I would think there wouldn't be that much recoverable.
Wow total of 13 AC lost, 5 shot down over China, 1 lost during an mission, 7 lost on training missions, according to Wikipedia, which the article is an interesting read.
https://en.m.wikipedia.org/wiki/Black_Cat_SquadronList of ROC U-2 aircraft lost
Shot down over mainland China
September 9, 1962: U-2C N.378 - Major Chen Huai (killed)
November 1, 1963: U-2C N.355 - Major Yeh Changti (captured, released in 1982), shot down by Yue Zhenghua and his Second Battalion
July 7, 1964: U-2G N.362 - Lt. Colonel Lee Nanpin (killed), shot down over Fujian by Yue Zhenghua and his Second Battalion
January 10, 1965: U-2C N.358 (56-6691) - Major Chang Liyi (captured, released in 1982), shot down over Baotou by Wang Lin and his First Battalion
September 8, 1967: U-2A N.373 - Captain Huang Jungpei (killed), shot down over Jiaxing by Xia Cunfeng and the 14th Battalion, first success by a Chinese-made surface-to-air missile
Lost due to technical failure during operational missions:
May 16, 1969: model and number unknown - Major Chang Hsieh (killed)
Lost during training missions:
March 19, 1961: U-2C N.351 - Major Chih Yaohua (killed)
March 23, 1964: U-2F N.356 - Captain Liang Tehpei (killed)
October 22, 1965: U-2A N.352 - Major Wang Chengwen (killed)
February 17, 1966: U-2F N.372 - Captain Wu Tsaishi (killed)
March 22, 1966: model and number unknown - Captain Fan Hungdi (survived)
June 21, 1966: U-2C N.384 - Major Yu Chingchang (killed)
November 24, 1970: U-2R N.057 - Major Huang Chihsien (killed)